P0403Low Severity
Auxiliary Emission Controls Malfunction (Circuit 0403)
This diagnostic trouble code indicates a malfunction in the associated component circuit.
Common Symptoms of P0403
- Check Engine Light (CEL) Illumination
- Potential decrease in auxiliary emission controls efficiency
- Engine performance issues related to circuit 0403
- Possible stall or rough idle
What Causes the P0403 Code?
- Faulty sensor or actuator in auxiliary emission controls
- Corroded, broken, or shorted wiring harness
- Poor electrical connection
- In rare cases, a failing Engine Control Module (ECM)
How serious is the P0403 code?
Because this code has a low severity level, it is highly recommended to address it promptly. Driving with an active P0403 fault can lead to secondary component failures and decreased fuel economy.
How do you definitively diagnose and fix P0403?
To accurately diagnose the P0403 fault code, you need the exact OEM wiring diagram and diagnostic test procedures for your specific vehicle. Create an Auto Fix Data account to instantly pull the factory diagrams for this fault.
Fix P0403 Now
Access the OEM repair manual and interactive wiring diagram to diagnose this exact code.
- Pin-to-pin wiring diagrams
- Component testing steps
- Technical Service Bulletins
- Identifix confirmed fixes
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P0003
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P0004
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P0005
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P0006
Fuel and Air Metering System Malfunction (Circuit 0006)